In the recent years, substantial attention has been directed to real time communication over packet switched communication networks like the Internet. In real time communication, such as audio and video streaming, timeliness and low latency can be more important than reliability of the packet streaming/transport. As communications networks are made up of a plurality of nodes that communicate over communication links that transfer information, the performance of the packet transport is impacted by packet delay variation in the network, and can suffer from buffer delay, head-of-line blocking delay, and priority inversion, which will have effect on timing sensitive signals such as IEEE1588/PTP (standard for a Precision Clock Synchronization Protocol for Networked Measurement and Control Systems). In the packet data networks transport, data is delivered over the network in packets. The packets are routed via intermediate nodes of the network, i.e. packets switches or routers, which each subjects the packets to delay due to internal processing, buffering and retransmission at intermediate switches. Intrinsic delay characteristics of a node in a communication network include input stage delay which is the time required for classification and admission control. Another primary source of the delay variations of the packet network is output queuing delay, which is caused as packets arrive at a switch or router when the exit port is blocked by other packets, in which case the incoming packet has to be queued/buffered. The buffering and queuing causes a variable delay and throughput which depends on the network's capacity and the traffic load on the network. In FIG. 1 an incoming packet stream B is illustrated being buffered in a typical buffer 100 before being further retransmitted as indicated by the flow arrows in the figure. Buffer 100 may be a dedicated input or output packet/frame buffer of a network node, e.g. a switch. Packets of a buffer are normally forwarded through the network node using a first-in, first out manner. In order to minimize the impact from the packet network using e.g. PTP packets specific algorithms can be implemented at a client, to allow the packets to be forwarded according to some scheduling discipline for fair queuing, traffic shaping, or for differentiated or guaranteed quality of service, such as weighted fair queuing or leaky bucket.